When you click on image in Ideabook, photo opens in full screen. Hover over the photo and on the bottom you'll see choices like: Save to Ideabook, Email, Ask Question. Click on Email and in popup window enter email you want to send it to and click Send button. You can also copy the image URL and paste it in your email.

But it still sends only a link, not the photo, right? Can I save a photo to a mobile device to view on the job sitecwhere thete is no intetnet connection?

Yes, it only sends the URL of the image. The only way as far as I am aware to save or copy the image is to go to ideabook, click Edit tab and then you can right-click the image and select in drop-down what you want to do with it. You can copy the image and paste it directly to your email body or you can save the image to your HD. Problem with this is that the image going to be only about 270x270 pixels. It's not possible to do the same with large image opened in lightbox view. There you can only select and copy embed code. Wish Houzz allowed us to copy or save large image in lightbox view also.